Centrifugal mold filling apparatus



Jan. 17, 1933. w, u z 1,894,877

' CENTRIFUGAL MOLD FILLING APPARATUS Filed May 2, 1931 Fig. 4. 3.9 49 34 132 "35 Patented Jan. 17, 1933 UNITED STATES PATENT OFFICE WILHELM KUBZE, F HANOVER, GERMANY, ASSIGNOB T0 LARGE AIWD GEILEN, OF HALLE, SAALE, GERMANY, A GERMAN FIRE cnurmuean norm rmme arrmrus Application filed my 2, 1931, Serial No.

Applications have been filed in Germany, May 26, 1928, and Feb. 28, 1929.

This invention relates to apparatus for filling sand into molds, and particularly into 6 mold boxes, which are used in foundries.

It has already been recognized that it is imortant, when the foundry sand is introduced into the mold box, to prevent, as far as pos- 'sible, the simultaneous introduction of air.

' Hitherto, however, experiments in this respect have not led to any useful results.

In accordance with the invention, apparatus is provided, b means of which a shower of foundry san' ,'substantially free from air, is arran ed to be thrown with great force into the mold boxes, so that the finished molds are very firm and homogeneous. Such apparatus may comprise rapidly-revolving, convex ,(rearwardly curved projection blades arranged in a casing, w ich propel the air before them outwards through apertures in the casing, the foundry sand being introduced immediately above the projection opening of :the casing by means of a worm conveyer. In this way, at the moment when the blades strike the sand, the air in front of the plates has already been almost completely removed. Insofar as there is still some air remaining in front of the blades after the latter have encountered the stream of sand supplied, this air is arranged to be conveyed inwardly and be removed therefrom, the blades engaging the sand only at their outer ends. By arranging the. sand supply just a above the projection opening, a very even shower of sand is thrown forcibly out of the apparatus.

The air which is still in front of the blades when the projection of sand takes place may be removed through an air a erturev and damper, which are provided ad acent to the projection opening of the casing.

The constant supply of sand under pressure to the rojection blades is essential for the removaf of air which would be detrimental tothe manufacture of the molds, and for regular operation of the apparatus; This is effected, in accordance with one constructional embodiment of the invention, by means of a worm conveyer located in a cond iit se- 584,851, and in Germany lay 26, 1928.

tional embodiment of the invention is illustrated, Figure 1 being a front elevation, Figure 2 a artial section on line II-II of Fig. 1, and igure 3 a plan view of Fig. 1.

.The box-shaped frame 1 of the machine comprises a table 2 ,on to which the foundry sand is cast, a pro ection casing 3, in which is located a projection opening 4, sand-supply members, which are described hereinafter, and the driving mechanism. In the floor of the table 2, over which scrapers 17 are adapted to rotate, an opening 6 covered by a sieve 5 is located, this opening leading to a vertical hopper 7. In the hopper 7 is provided a distributor 8, which consists of a shaft 45, provided with one or more raking arms 46 thereon, one only being shown. Shaft 45 is driven through abelt or chain 49 from shaft 21, hereinafter referred to. The hopper 7 leads into a conduit 9, in which is located a worm 10. The conduit 9 is secured to the casing 3 just above the projection opening 4.

In the casing 3 is located a rotatable disc 11, to which are secured two or more projection blades 12, formed convex in the direction of rotation. On the circumference of the casing apertures 13 are provided, and just above the sand supply conduit 9 is an air vent 14. Adjacent to the projection opening 4, the casin contains an air aperture 15 and a damper p ate 16, which is U-shaped in crosssection, see Fig. -2. I

The apparatus, as illustrated by way of example, is driven by an electric motor 18, the speed of which may be regulated between wide limits. On shaft 28 of the motor is a pulley 29, which drives pulley 30, mounted on shaft 20, carryin the disc 11, through belt 19. A second sha 21 is driven from shaft by belt 22 and pulleys 31 and 32. A bevel gear 33 is keyed on shaft 21 and drives bevel gear 34 on vertical'shaft 39, which drives the scrapers 17 through bevel gears 40 and 41, shaft 42 and bevel ears 43 and 44. Bevel gear 34 meshes with vel gear 35, the hub of which carries spur teeth 36, in mesh with spur gear 37 on shaft 38, which carries the worm 10. In order that the entire apparatus may be readilytrans orted and oscillated, trunnions 23 are provi ed on the frame 1 of the apps;

ratus.

When the ap aratus is operated without sand being supp ied, the rotatable disc 11 acts with its blades 12 as an air propeller. The air propelled by the blades passes outwards through the apertures 13 and the vent 14. When foundry sand is conveyed to the conduit 9 by the worm 10, the blades 12 strike the sand with their outer ends, after the greater part of 15 the air propelled by the blades has been removed. When the blades strike the sand the latter is projected through the projection opening 4 and air thrown out by the blades near the projection opening after the sand 2 has left the blades will strike the damper Pith the sand, through said adjacent air out- In testimony whereof I have signed my name to this specification.

WILHELM KURZE.

plate 16 and be deflected laterally through the latter which is hollow to the extreme left side (Figure 1) of the apparatus,or be deflected by t e damper plate 16 through aperture 15, a suction being exerted at the aperture 15 in view of the passage of air from the interior of the casing 3 through the aperture in the lower part of the casing and apertures 26 and 27. The projection opening 4 in the casing is substantially tangential to the circular path of the outer ends of the blades. As the sand supply conduit 9 is located immediately above the rejection opening 4 and extends substantially radially to the casing, a shower of sand is forcibly thrown out, which is substantially free from air.

The apparatus illustrated in the drawin is to be considered only as a constructiona example. For instance, the number of pro- .jection blades 12 may evidently be altered. The sand may also be cast initially into the hopper 7 by means of. a chain conveyer or a screw conveyer instead of from the table 2 rovided with scrapers 17. The projection lades 12 may be integral with the disc 11 or alternatively connected to it. An interchangeable armour-plate 24 may be rovided Y adjacent the projection opening 4 .o the easbe evident to those skilled in the art, may be made without exceeding the scope of the invention.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

In centrifugal mold-fillingapparatus, the

mg. a These and other modifications, which will of said tangential outlet; rotary means 1n said casing to drive air out of the same and to project the sand from said tangential outlet, and a damper plate rojectmg into said as outlet to d ect air, carried along 

